Acronym for Standards Eastern Automatic Computer. The first stored-program electronic digital computer to become operational in the USA, in 1950. (Compare Manchester Mark I, EDSAC, EDVAC.) It was one of two different pioneer machines developed by the National Bureau of Standards: SEAC was installed in Washington, and the other, called SWAC (Standards Western Automatic Computer), in Los Angeles. Like EDSAC and EDVAC, SEAC used mercury delay line memory.